If you had any doubts about whether eating early helps reducing nighttime heartburn look at this link with scientific article from Centre Hospitalier Universitaire Vaudois, Gastroentérologie, Lausanne, Switzerland.
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1434162
Abstract: “This study examines whether eating food at different times has differential effects on intragastric pH. Experiments were done in 23 healthy volunteers (12 men). Intragastric acidity was monitored by ambulatory 22 hour pH-metry. Composition of meals was standardised: breakfast and lunch at 7 am and 12 noon respectively, and dinner at 6 or 9 pm, in random order. The time of going to bed and getting up was also standardised. With early dinner nocturnal pH was higher, than with late dinner (pH median: 1.67 and 1.39, p less than 0.001). During the remaining time periods, pH values were similar. Thus early dinner may be helpful in conditions where low intragastric acidity is desirable.”
It clearly proves that if you go to bed at 11pm and have later dinner at 9pm your pH will be 1.39. If you have early dinner at 6pm than your pH will be 1.69 or 20% lower.
Please note that the higher the pH the lower the acidity. Thus pH of 1 is very acid while pH of 5 is very alcaline.
Conclusion: moving your dinner 3 hours early will reduce your nighttime heartburn 20%… Of course your mileage may vary but trend is quite obvious.
Moving dinner even earlier won’t help much since you’ll get hungry by the time you need to get to sleep.
This study is also confirmed by many advices I get from the books and internet. Heartburn and eating late has a very close connection. Just dealing with late food cravings could make a significant difference in how heartburn affects your lifestyle.